package mvcCalculator;
import java.math.BigInteger;
public class CalcModel {
	   private static final String INITIAL_VALUE = "0";
	    
	    //... Member variable defining state of calculator.
	    private BigInteger m_total;  // The total current value state.
	    
	    //============================================================== constructor
	    /** Constructor */
	    CalcModel() {
	        reset();
	    }
	    
	    //==================================================================== reset
	    /** Reset to initial value. */
	    public void reset() {
	        m_total = new BigInteger(INITIAL_VALUE);
	    }
	    
	    //=============================================================== multiplyBy
	    /** Multiply current total by a number.
	    *@param operand Number (as string) to multiply total by.
	    */
	    public void multiplyBy(String operand) {
	        m_total = m_total.multiply(new BigInteger(operand));
	    }
	    
	    //================================================================= setValue
	    /** Set the total value. 
	    *@param value New value that should be used for the calculator total. 
	    */
	    public void setValue(String value) {
	        m_total = new BigInteger(value);
	    }
	    
	    //================================================================= getValue
	    /** Return current calculator total. */
	    public String getValue() {
	        return m_total.toString();
	    }
}
